A tale Robert Kanigel repeated a couple of times during his recent visit to Madras to launch the 125th birthday celebrations of mathematical genius Ramanujan related to his first visit to Madras in 1988 to start following the Ramanujan trail on the ground as he got down to working on the mathematician's biography.

That November day he landed from London was a bandh day in Madras and the airport was virtually deserted. There was a lone auto rickshaw with a passenger in it and another person haggling to get aboard. That person was Viswanathan Venkataraman, who had also arrived from London. When he noticed the forlorn foreigner wondering what he should do, Viswanathan told him that the only way to get to the city was to squeeze in with them. And Kanigal joined them for that ride in a sardine tin.

During the ride, Viswanathan discovered that Kanigal was not a tourist but a well known writer who was working on Ramanujan's biography. “What a coincidence,” remarked Viswanathan, “I am the grandson of S. Narayana Aiyar with whom Ramanujan worked in the Port Trust.” No, it's not coincidence, it's Providence, a surprised Kanigal enthusiastically replied. And so began Kanigal's first steps in Madras that led to The Man Who Knew Infinity: A Life of the Genius Ramanujan.